Method of making an expanded metal fin for an oil cooler



July 22, 1969 R. s. JOHNSON 3,456,320

METHOD OF MAKING AN EXPANDED METAL FIN FOR AN OIL COOLER Filed 001;. 5, 1966 2 Sheets-Sheet 1 g2 INVENTOR BY Wm 60ml.

ATTORNEYS- July 22, 1969 R. s. JOHNSON METHOD OF MAKING AN EXPANDED METAL FIN FOR AN OIL COOLER Filfid Oct. 5, 1966 2 Sheets-Sheet 2 3,456,320 METHOD OF MAKING AN EXPANDED METAL FIN FOR AN OIL COOLER Richard S. Johnson, Racine, Wis., assignor to Modine Manufacturing Company, a corporation of Wisconsin Filed Oct. 5, 1966, Ser. No. 584,490 Int. Cl. B21d 53/02; B23p 15/26 US. Cl. 29157.3 2 Claims ABSTRACT OF THE DISCLOSURE One of the features of this invention is to provide an improved method of making an expanded metal fin of the type set out in the above abstract.

Other features and advantages of the invention will be apparent from the following description of one embodiment thereof taken in conjunction with the accompanying drawings. Of the drawings:

FIGURE 1 is a side elevational view of an oil cooler embodying the invention with the cover plate removed for clarity of illustration.

FIGURE 2 in a longitudinal sectional view taken substantially along line 22 of FIGURE 1.

FIGURE 3 is a fragmentary sectional view taken substantially along line 3--3 of FIGURE 2.

FIGURE 4 is a fragmentary perspective view of a sheet of deformable metal containing slits preparatory to expanding the metal.

FIGURE 5 is a semi-diagrammatic side elevational view partially in section of an apparatus for expnding the metal of FIGURE 4 and simultaneously forming a fin embodying the invention.

FIGURE 6 is a sectional elevational view taken substantially along line 6-6 of FIGURE 5.

FIGURE 7 is an enlarged plan view of a section of the expanded metal.

In the embodiment of FIGURES 13 the oil cooler 10 comprises an elongated frame 11 attached to an internal combustion engine block 12 as by spaced bolts 13. The frame 11 contains a chamber 14 at one end communicating by way of an opening 15 with the lubricating section of the engine. The other end of the frame 11 contains a similar internal chamber 16 communicating with another spaced section of the oil chamber by way of an opening 17.

Extending between the end chambers 14 and 16 is an elongated conduit 18 of flattened oval cross section as shown in FIGURE 3 through which oil flows for cooling thereof. The conduit 18 is cooled by liquid coolant from the engine block 12 as this coolant flows from the block to surround the conduit 18 by way of an elongated opening 19. The side of the oil cooler 10 opposite the opening 3,456,329 Patented July 22, 1969 ice 19 is sealed by means of a cover plate 20 held in position by means of the spaced bolts 13.

Located within the conduit 18 and extending between the end chambers 14 and 16 is an expanded metal fin 21 having corrugations extending longitudinally of the conduit and dividing the conduit into side-by-side channels 22 through which the oil fiows while being cooled by the coolant surrounding it from the opening 19. Because of the expanded metal construction, as shown by the section of the fin 21 in FIGURE 7, the oil in adjacent channels 22 mingles back and forth by way of the openings 23 in the expanded metal.

As can be seen from FIGURE 3 the channels 22 are preferably substantially parallel and substantially equally spaced in the fin. In the preferred construction the conduit 18 has opposite sides 24 and the expanded metal fin 21 has alternate ridges and grooves with the extremities of the ridges being in contact with one of the sides 24 and the other extremities being in contact with the other side 24. In this preferred construction, these extremities are substantially flat and coplanar, as shown in FIGURE 3, so as to make good heat transfer engagement with the sides 24 of the oil cooling conduit 18.

FIGURES 4-7 illustrate one method of making the oil cooler fin described above. As shown in FIGURE 4, a sheet 25 of deformable metal such as aluminum or copper is provided wtih longitudinal slits 26 dividing the sheet into a plurality of strands 27 and connecting bridges 28. The slits 26 may be provided by any means desired such as by stamping or by the use of cutting rollers or wheels.

In expanding the sheet 25 to provide the openings illus trated in FIGURE 7, the sheet of course must be stretched laterally or in the direction of the double headed arrow 29 of FIGURE 4. This is accomplished in the present invention simultaneously with the corrugating of the sheet to produce the fin 21. In the apparatus as illustrated in FIGURES 5 and 6 the sheet 25 is directed between cooperating rolls 30 and 31 having intermeshing parallel annular ridges 32 and 33. These ridges 32 and 33 which have flat tops similar to the fiat peaks 34 of the fin 21 that is produced therewith simultaneously corrugated the sheet 25 into the shape of the fin and also deform the slit metal laterally to open up the slits and form the expanded metal. This is accomplished in the present invention by having the cooperating end ridges on the two rolls grasp the side edges of the sheet, as shown in FIGURE 6, so that as the intermeidate ridges 32 and 33 deform the sheet into its corrugated shape they also stretch the sheet to produce the expanded metal arrangement illustrated in FIGURE 7. In other words, as the silt sheet 25 passes into the rolls from the left, as shown in FIGURE 5, it is deformed into the corrugated shape while restricting narrowing of the sheet. Therefore, the corrugated fin structure 21 coming from the rolls, as shown in FIGURE 5, is approximately the same width as the unexpanded sheet 25 going into the rolls.

Having described by invention as related to the embodiment shown in the accompanying drawings, it is my intention that the invention be not limited by any of the details of description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

I claim:

1. The method of making an expanded metal fin adapted to be positioned in an oil cooler conduit having a pair of opposite walls to divide the conduit into side-byside channels through which the oil flows and mingles by way of the openings in said expanded metal, comprising: providing a sheet of deformable metal having longitudinal slits dividing the sheet into a plurality of strands and connecting bridges; simultaneously corrugating said sheet into adjacent corrugations having crests while deforming the sheet laterally to open up said slits; and shaping said crests to fit snugly against said opposite walls.

2. The method of claim 1 wherein said simultaneous corrugating and deforming is accomplished by grasping 4 the side edges of said sheet and stretching the sheet between the edges into angularly corrugated cross sectional shape having substantially flat crests.

References Cited UNITED STATES PATENTS 2,334,243 11/1943 Bowers 29-1635 X 2,643,863 6/1953 Buschow 29-1573 X 2,989,145 6/1961 Goodloe 29163.5 X 10 3,083,662 4/1963 Zeidler 113116 THOMAS H. EAGER, Primary Examiner US. Cl. X.R. 

